Airbags and airbag systems have been implemented and used on motor vehicles for many years as a safety device. These systems are designed such that, in the event of a crash or accident, an airbag will be inflated and positioned adjacent the vehicle occupant. Such positioning of the airbag prevents the vehicle occupant from harmful impact with the steering wheel, the dashboard, or other portions of the vehicle interior. Because airbag systems have been credited with saving many lives, the inclusion of airbag systems on new vehicles is now a requirement in many countries.
In order to deploy the airbag, the airbag system will generally include an inflator. An inflator is a device that is capable of rapidly producing/channeling large quantities of inflation gas into the airbag during deployment. This influx of gas into the airbag inflates the airbag and causes the airbag to become positioned on the vehicle interior.
In order to rapidly deploy the airbag, the inflator will generally include an initiator. The initiator generally includes a combustible material that is ignited upon receipt of the appropriate signal. Such ignition of the combustible material, in turn, creates a pressure change in the inflator and results in deployment of the inflator.
The combustible material found in the initiator is generally housed within a “cup” (which is sometimes called a “pyrotechnic cup”). The cup is generally a wall that surrounds the combustible material. Unfortunately, during ignition/combustion of the combustible material, the pressure change caused by combustion often causes the cup to fragment into small pieces. Obviously, it is undesirable to have fragments of the cup enter the airbag; accordingly, the inflator must be designed to ensure that these fragments are retained within the inflator and not allowed to enter the airbag.
In order to capture fragments produced by ignition, many currently constructed initiators will include a glass to metal seal (“GTMS”) header with a laser welded charge holder. This charge holder serves as a pressure vessel that reduces the stress in the cup and prevents the cup from fragmenting. Other inflators also add a cup retention device, such as a screen, to retain fragments of the pyrotechnic cup. Unfortunately, these charge holders and/or cup retention devices increase the cost of the inflator. Accordingly, there is a need in the art for a new type of inflator that does not require charge holders/cup retention devices, yet still prevents cup fragments from entering the airbag. Such a device is disclosed herein.